1. Field of the Invention
The invention is related to the field of pneumatic controls, and in particular, to an improved valve island.
2. Description of the Prior Art
Valve islands are typically considered to be a group of electrically operated pneumatic valves mounted on a common base with a common electrical wireway. Valve islands may also be manually or pneumatically controlled. FIG. 1 is an isometric view of a typical valve island. Valve island 100 comprises a plurality of sub-bases 102, two end plates 104 and 105, with one or both end plates having multipole or fieldbus connections 106, a plurality of valves where the plurality of valves may be single solenoid valves 116 or double solenoid valves 118, the valves have a plurality of solenoids 108 attached, optional sandwich plates and base accessories 114, and a mounting bracket 112. The plurality of sub-bases 102 are joined together in a row with one of the end plates attached at each end of the row of sub-bases. The plurality of valves are mounted on top of the plurality of sub-bases 102.
One of the advantages of a valve island is that they can be expanded by incrementally adding a single or double valve stations. FIG. 2 is a partially exploded view of a typical valve island. Valve island 200 has a plurality of sub-bases 202, two end plates 204 and 205, a single add on station 203, a plurality of single solenoid valves 216, two double solenoid valves 218, screws 220, gasket 222, expansion PC board 224, a plurality of solenoids 208, and a main PC board 230 installed in the electronic raceway of the valve island 200. Screws 220 are used to couple the sub-bases together and attach the sub-bases to the end plates 204 and 205. Gasket 222 helps form a seal between the sub-bases 202 and the single add on station 203. A gasket (not shown) may also be used between single add on station 203 and end plate 205. PC board 224 is installed into electronic raceway 226 and is used to control the valve attached to the single add on station 203. Screws 228 are used to attach a valve to the single add on station 203.
FIG. 3 is an isometric view of main PC board 330 being inserted into the electronic raceway 326 of a valve island 300. Electrical connectors 332 are attached to main PC board 330 and are used to mate with or couple the main PC board 330 with the valves (not shown) attached to the top of the sub-bases 302 and 303.
Current valve islands have a number of problems. One problem is the complexity of the fluid passageways that run between and connect the various components of the valve island. The fluid passageways are difficult to manufacture and may limit the minimum size of the valve components.
Therefore there is a need for an improved valve island.